A Framework for Evaluating Early-Stage Human - of Marcus Hutter

fer to non-linguistic experience, then in NARS it is possible
to link “Garfield” to related visual images and operation sequences,
so as to enrich its meaning. However, it is important
to understand that both linguistic experience and nonlinguistic
experience are special cases of experience, and the
latter is not more “real” than the former.
In the previous discussions, many people implicitly suppose
that linguistic experience is nothing but “Dictionary-
Go-Round” (Harnad, 1990) or “Chinese Room” (Searle,
1980), and only non-linguistic sensorimotor experience can
give symbols meaning. This is a misconception coming
from traditional semantics, which determines meaning by
referred object, so that an image of the object seems to be
closer to the “real thing” than a verbal description. NARS’
experience in Chinese is different from the content of a
Chinese-Chinese dictionary, because a dictionary is static,
while the experience of a system extends in time, in which
the system gets feedback from its environment as consequences
of its actions, i.e., output sentences in Chinese. To
the system, its experience contains all the information it can
get from the environment. Therefore, the system’s processing
is not “purely formal” in the sense that the meaning of
the symbols can be assigned arbitrarily by an outside observer.
Instead, to the system, the relations among the symbols
are what give them meaning. A more detailed discussion
on this misconception can be found in (Wang, 2007),
and will not be repeated here.
In summary, NARS satisfies the two requirements of embodiment
introduced previously:
Working in real world: This requirement is satisfied by
the assumption of insufficiency in knowledge and resources.
Having grounded meaning: This requirement is satisfied
by the experience-grounded semantics.
Difference in Embodiment
Of course, to say an implementation of NARS running in
a laptop computer is “already embodied”, it does not mean
that it is embodied in exactly the same form as a human mind
operating in a human body. However, here the difference is
not between “disembodied” and “embodied”, but between
different forms of embodiment.
As explained previously, every concrete system interacts
with its environment in one or multiple modalities. For a human
being, major modalities include vision, audition, tactile,
etc.; for a robot, they include some human-like ones, but also
non-human modalities like ultrasonic; for an ordinary computer,
they directly communicate electronically, and also can
have optional modalities like tactile (keyboard and various
pointing devices), audition (microphone), vision (camera),
though they are not used in the same form as in a human
body.
In each modality, the system’s experience is constructed
from certain “primes” or “atoms” that is the smallest units
the system can recognize and distinguish. The system’s processing
of its experience is usually carried out on their compound
“patterns” that are much larger in scale, though short
in details. If the patterns are further abstracted, they can
177
even become modality-independent “symbols”. This is the
usual level of description for linguistic experience, where
the original modality of a pattern, with all of its modalityspecific
details, is ignored in the processing of the message.
However, this treatment does not necessarily make the system
disembodied, because the symbols still comes from the
system’s experience, and can be processed in an experiencedependent
manner.
What makes the traditional symbolic AI system disembodied
is that the symbols are not only abstracted to become
modality-independent, but also experience-independent, in
the sense that the system’s processing of the symbol is fully
determined by the system’s design, and have little to do with
its history. In this way, the system’s body becomes completely
irrelevant, even though literally speaking the system
exists in a body all the time.
On the contrary, linguistic experience does not exclude
the body from the picture. For a system that only interact
with its environment in a language, its experience is linguistic
and amodal, in the sense that the relevant modality is not
explicitly marked in the description of the system’s experience.
However, what experience the system can get is still
partially determined by the modality that carries out the interaction,
and therefore, by the body of the system. As far
as the system’s behavior is experience-dependent, it is also
body-dependent, or embodied.
Different bodies give a system different experiences and
behaviors, because they usually have different sensors and
operators, as well as different sensitivity and efficiency on
different patterns in the experience and the behavior. Consequently,
even when they are put into the same environment,
they will have different experience, and therefore different
thoughts and behaviors. According to experience-grounded
semantics, the meaning of a concept depends on the system’s
experience on the concept, as well as on the possible operations
related to the concept, so any change in the system’s
body will more or less change the system’s mind.
For example, at the current stage, the experience of
NARS is purely linguistic, so the meaning of a concept like
‘Garfield’ only depends on its experienced relations with
other concepts, like ‘cat’, ‘cartoon character’, ‘comic strip’,
‘lazy’, and so on. In the future, if the system’s experience is
extended to include visual and tactile components, the meaning
of ‘Garfield’ will include additional relations with patterns
in those modalities, and therefore become closer to the
meaning of ‘Garfield’ in a typical human mind. Therefore,
NARS implemented in a laptop and NARS implemented in a
robot will probably associate different meaning to the same
term, even though these meanings may have overlap.
However, it is wrong to say that the concept of ‘Garfield’
is meaningful or grounded if and only if it is used by a robot.
There are two common misconceptions on this issue. One is
to only take sensorimotor experience as real, and refuse to
accept linguistic experience; and the other is to take human
experience as the standard to judge the intelligence of other
systems. As argued previously, every linguistic experience
must be based on some sensorimotor experience, and though
the latter is omitted in the description, it does not make the
former less ‘real’ in any sense. Though “behave according